HEAT TRANSFER IN ROTATING CHANNEL WITH INCLINED PIN-FINS

摘要

This study is to examine experimentally the effects of pin inclination and pin height-to-diameter ratio on the heat/mass transfer characteristics in a pin-fin channel with and without rotation. The test model consists of staggered pin-fin arrays with an inter-pin spacing of 2.5 times of the pin-diameter (S/D=2.5) in both longitudinal and transverse directions. Detailed local heat/mass transfer coefficients on the two principal surfaces of rotating channel are measured using the naphthalene sublimation technique. The inclined angles (θ) studied are 60° and 90°. The pin height-to-diameter ratio (H_p/D_p) ranges from 2 to 4. The Reynolds number is fixed at 7.0 × 10~3 with two Rotation numbers (0.0 and 0.2). The measured data show that the overall array heat/mass transfer decreases with the angle of inclination relative to the vertical orientation. The overall array averaged as well as the row-resolved heat/mass transfer increases with an increase in H_p/D_p Rotation generally results in higher heat/mass transfer than the corresponding stationary case. The non-uniformity or redistribution of heat/mass transfer induced by the Coriolis force generally perceived in a ribbed or smooth channel is less evident in a pin-fin channel.